One of the hazards of manned spaceflight is an air leak in an air-pressurized spacecraft which may, in some cases, compel an evacuation of the spacecraft. On large spacecraft, such as the International Space Station (ISS), leaks on the order of 0.25 inches diameter or less may provide opportunities for repair, while larger leaks may not. Some leaks may go undetected for an undesirable period, during which the size of the leaking aperture may erode to become a larger leak. Prognostic temporal parameters relating to the leak are desired to support decision-making by the mission commander and ground support personnel. Current methods and apparatus do not provide the information desired.
Research has been done on rates at which air will leak from a spacecraft, given a particular feeding volume and leak aperture size. NASA, in particular, has done research in the field of spacecraft air leaks and produced pressure vs. time curves for leaks of various aperture sizes as functions of feeding volume. However, this research has yet to find practical application.
During a postulated air leak event in a manned spacecraft, the attention of the crew may be highly focused on immediately responsive measures and verbal communications to ground support personnel may be uninformative or absent. The ground support personnel may need information on crew activities to ensure quality support. For example, the flight crew of the ISS may close hatches (which have no dedicated telemetry) between ISS compartments and fail to communicate this to ground personnel. Ground personnel may be able to contribute to the solution if they have adequate information, but, without additional information, may not know which hatches have been closed.
Accordingly, it is desirable to provide a system and a method to detect a leak, determine the size of the leak, determine a rate of change of the size of the leak, and to detect hatch openings and closures. In addition, it is desirable to communicate this information in a timely manner to the flight crew and to ground personnel. Furthermore, other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description of the invention and the appended claims, taken in conjunction with the accompanying drawings and this background of the invention.